1). Field of the Invention
This invention relates generally to a method of manufacturing a plurality of electronic assemblies, and more specifically to improvements in fabrication at water level.
2). Discussion of Related Art
Integrated circuits are usually manufactured in and on semiconductor wafers. Such an integrated circuit has millions of tiny electronic components such as transistors, capacitors, and diodes that are interconnected with conductive lines, plugs, and vias.
One wafer typically has an array of identical circuits formed thereon. The wafer was is then “singulated” or “diced” by directing a blade through scribe streets between the integrated circuits, thereby separating the wafer into the individual dice. Each die is then separately mounted to a respective carrier substrate for purposes of providing structural rigidity to the die and to provide power, ground, and signals to and from the die.
A plurality of conductive terminals are formed on the integrated circuits before the wafer is singulated. Such terminals are typically solder bumps that are formed according to a conventional “controlled collapsed chip connect” (C4) process. After the wafer is singulated, each one of the bumps is placed on a respective contact of the carrier substrate. The bumps are then reflowed so that they are structurally and electrically connected to the contacts. The process is repeated to connect each die singulated from the wafer to a separate carrier substrate to form separate electronic assemblies. Downstream fabrication is then separately carried out on each separate electronic assembly.